Ovarian programming of gamete progression and maturation in the female genital tract

Whilst the rate of displacement and migration of sperm cells in the female reproductive tract of rodents, farm animals and humans has attracted attention for at least 50 years, the overriding purpose of sperm transport has not always been kept in focus. This report is concerned with spermatozoa that can penetrate the egg investments and promote formation of a zygote, judgements involving a surgical approach and subsequent phase-contrast microscopy. A minimum period of 6–8 hours was required for such spermatozoa to be established in the oviducts in sheep and cows mated at the onset of oestrus. Sperm were then arrested in the caudal 12 cm of the isthmus for 17–18 hours or more until just before the moment of ovulation, when they were activated and displaced onwards to the site of fertilization at the ampullary-isthmic junction. The time-scale of these events differs in pigs as a result of the intra-uterine site of ejaculation and the 40-hour interval between the onset of oestrus and ovulation, but the pre-ovulatory sequestering of viable spermatozoa in the caudal tip of the oviduct is conspicuous for 36 hours or more. This function of the oviduct appears to be under local control from ovarian follicular hormones and, as judged by sperm motility and membranous changes, so does the process of capacitation. Completion of capacitation is interpreted as a peri-ovulatory event.     

Effect of secretions from female genital tract on some vitality indexes of spermatozoa]

The survival time and speed of movement of washed bull spermatozoa suspended in Peterson buffer (1:10) and secretions from various parts of the genital tracts of cows (Cervix, horns, oviductus) collected in different stages of the estrous cycle (early luteal, full luteal, follicular) were determined. Survival time of the spermatozoa was determined at 46.5 degrees under a microscopic using the Beck and Salisbury method. The speed of movement was measured at 37 degrees in a Burker hemocytometer. The survival time and speed of movement of the spermatozoa were stimulated by secretions in the follicular and early luteal stages. Secretions during the full luteal stage depressed these figures. Secretions taken from different parts of the genital tract did not show any significant differences in stimulatory action.     

Distribution of carnitine and acylcarnitine in the hamster epididymis and in epididymal spermatozoa during maturation

The highest levels of carnitine and acylcarnitine were found in the cauda epididymidis, and spermatozoa from the cauda contained greater amounts of total carnitine (free carnitine plus acylcarnitine) than those removed from the corpus or caput epididymidis. Spermatozoa from the distal cauda contained significantly greater amounts of both free and total carnitine than those removed from the proximal cauda epididymidis. The acylcarnitine:carnitine ratio was 1.7 and 0.37 in caput and cauda spermatozoa, respectively and 1.7 and 1.3 in caput and cauda fluid, respectively. It is suggested that the accumulation of carnitine is involved in sperm maturation and that acylcarnitine serves as an energy substrate for epididymal spermatozoa.     

Distribution and expression of phosphorylated histone H3 during porcine oocyte maturation

Phosphorylation modification of core histones is correlated well with diverse chromatin-based cell activities. However, its distribution pattern and primary roles during mammalian oocyte meiosis are still in dispute. In this study, by performing immunofluorescence and Western blotting, spatial distribution and temporal expression of phosphorylated serine 10 or 28 on histone H3 during porcine oocyte meiotic maturation were examined and distinct subcellular distribution patterns between them were presented. Low expression of phosphorylated H3/ser10 was detected in germinal vesicle. Importantly, following gradual dephosphorylation from germinal vesicle (GV) to late germinal vesicle (L-GV) stage, a transient phosphorylation at the periphery of condensed chromatin was re-established at early germinal vesicle breakdown (E-GVBD) stage, and then the dramatically increased signals covered whole chromosomes from pre-metaphase I (Pre-MI) to metaphase II (MII). Similarly, hypophosphorylation of serine 28 on histone H3 was also monitored from GV to E-GVBD, indicating dephosphorylation of histone H3 maybe involved in the regulation of meiotic resumption. Moreover, the rim staining on the chromosomes and high levels of H3/ser28 phosphorylation were observed in Pre-MI, MI, and MII stage oocytes. Based on above results, such stage-dependent dynamics of phosphorylation of H3/ser 10 and 28 may play specific roles during mammalian oocyte maturation.     

Amylase in human lungs and the female genital tract

Summary We investigated the localization of amylase in normal human lungs and the female genital tract using immunohistochemical and histochemical methods. Immunohistochemical procedures were applied to formaldehydefixed, paraffin-embedded specimens as well as to cryostat sections of periodate/lysine/paraformaldehyde (PLP)-fixed tissues. The starch-substrate-film method was used for the histochemical investigation of unfixed frozen sections. Amylase immunoreactivity was observed in ciliated epithelial cells of the bronchus and in serous cells of the bronchial glands but not in the alveolar epithelium. Immunoreactive amylase was also found in the cytoplasm of the ciliated epithelium of the fallopian tubes, especially in the apical part of the cytoplasm and in ciliary vesicles. Immunoreactive amylase was also found to be present in the surface epithelial cells and glands of the uterine cervix, as well as in the superficial part of the endometrial glands. The distribution of amylase activity revealed using histochemistry was similar to that observed in cryostat sections of PLP-fixed tissues after immunohistochemical staining. Amylase amtigenicity was better preserved in cryostat sections of PEP-fixed materials than in formaldehyde-fixed, paraffinembedded specimens. The results are discussed in relation to pulmonary and female-genital-tract diseases.This work was supported by a grant from the Tokyo Metropolitan Government     

女性生殖道微生态屏障

随着感染微生态学的发展,尤其是宿主-微生物相互作用的研究深入,越来越多的研究发现,新的微生态屏障在维持宿主健康方面发挥着重要作用。微生态屏障包括微生物屏障,机械屏障,免疫屏障和化学屏障四个部分。其中机械屏障是微生态屏障的基础,微生物屏障是微生态屏障的关键,免疫屏障是微生态屏障的核心,化学屏障是微生态屏障的有机组成部分。微生态屏障可维持宿主生境的微生态平衡,防止病原微生物的入侵和感染的发生。     

Peptide-immunoreactive nerves in the mammalian female genital tract

Summary Vasoactive intestinal polypeptide, substance P, neuropeptide Y and peptide histidine isoleucine immunoreactivities have been demonstrated in the female genitalia of rat, cat, mouse and guinea-pig using immunocytochemistry and radioimmunoassay. They were localized to nerves. Each type of immunoreactive nerve showed a distinct pattern of distribution, though all were associated to some degree with blood vessels and smooth muscle. Vasoactive intestinal polypeptide-immunoreactive and neuropeptide Y-immunoreactive nerves were the most abundant. Higher concentrations of peptides were detected in the female genitalia of the mouse than those of the other species studied. Vasoactive intestinal polypeptide-immunoreactive nerves were particularly concentrated in the cervix (89.1±17.2 pmol/g, mean±S.E.M.) and the uterus (57.4±14.8 pmol/g) of the mouse, while neuropeptide Y immunoreactivity was more abundant in the Fallopian tube of the mouse (31.6±11.8 pmol/g) and the vagina of the rat (38.6±4.8 pmol/g) than in other regions. Separate populations of ganglion cells in the paracervical ganglia were found to contain vasoactive intestinal polypeptide and neuropeptide Y immunoreactivities. Peptide histidine isoleucine-immunoreactive and vasoactive intestinal polypeptide-immunoreactive nerves were similarly distributed, but the former were much less frequent. Substance P-immunoreactive nerves were seen mainly beneath the epithelium of the vagina and were, in general, more numerous in the guinea-pig than in other species. The significance of these peptide-immunoreactive nerves in the female genital organ remains to be determined.Dr. Wang is on leave from The Institute of Acupuncture, The Academy of Chinese Traditional Medicine, Peking, China.